title: Functional expression of the murine D2, D3, and D4 dopamine receptors in Xenopus laevis oocytes.
abstract: The different murine D2-type dopamine receptors (D2L, D2S, D3L, D3S, and D4) were expressed in Xenopus laevis oocytes. The D2-type receptors were all similarly and efficiently expressed in Xenopus oocytes and were shown to bind the D2 antagonist [125I]sulpride. They were all shown to activate Cl- influx upon agonist stimulation. Using the diagnostic inhibitor bumetanide, we were able to separate the Na+/K+/2Cl- cotransporter component of the Cl- influx from the total unidirectional Cl- influx. The D3L subtype was found to operate exclusively through the bumetanide-insensitive Cl- influx whereas the other D2-type receptors acted on the Na+/K+/2Cl- cotransporter as well. The pertussis toxin sensitivity of the receptor-activated chloride influx via the Na+/K+/2Cl- cotransporter varied between the various D2-type receptors showing that they may couple to different G proteins, and activate different second messenger systems.
authors.affiliation: Department of Immunology, The Weizmann Institute of Science, Rehovot, Israel.
authors.forename: B
authors.initials: B
authors.lastname: Skaaning Jensen
authors.forename: B
authors.initials: B
authors.lastname: Levavi-Sivan
authors.forename: C S
authors.initials: CS
authors.lastname: Fishburn
authors.forename: S
authors.initials: S
authors.lastname: Fuchs
mesh_terms: D000818:Animals; D002034:Bumetanide / Q000494:pharmacology; D002352:Carrier Proteins / Q000378:metabolism; D002712:Chlorides / Q000493:pharmacokinetics; D004298:Dopamine / Q000494:pharmacology; D018492:Dopamine Antagonists / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000378:metabolism; D005786:Gene Expression Regulation / Q000235:genetics*; D008845:Microinjections; D009865:Oocytes / Q000378:metabolism*; D037342:Pertussis Toxin; D011233:Precipitin Tests; D011954:Receptors, Dopamine / Q000145:classification / Q000378:metabolism*; D015398:Signal Transduction; D028021:Sodium-Potassium-Chloride Symporters; D014162:Transfection / Q000235:genetics; D010566:Virulence Factors, Bordetella / Q000494:pharmacology; D014982:Xenopus laevis
chemical_list: D002352:Carrier Proteins; D002712:Chlorides; D018492:Dopamine Antagonists; D011954:Receptors, Dopamine; D028021:Sodium-Potassium-Chloride Symporters; D010566:Virulence Factors, Bordetella; D002034:Bumetanide; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; D004298:Dopamine